Extracorporeal membrane oxygenation (ECMO) is a technique that uses a pump to drain blood from a body, circulate blood through a membrane lung, and return the oxygenated blood back into the body. Venoarterial (VA) ECMO is a simplified version of the heart-lung machine that assists native pulmonary and/or cardiac function. VA ECMO is composed of a drainage cannula in the venous system and a return cannula in the arterial system. Because VA ECMO can increase tissue perfusion by increasing the arterial blood flow, it is used to treat medically refractory cardiogenic shock or cardiac arrest. VA ECMO has a distinct physiology that is referred to as differential flows. It can cause several complications such as left ventricular distension with pulmonary edema, distal limb ischemia, bleeding, and thromboembolism. Physicians who are using this technology should be knowledgeable on the prevention and management of these complications. We review the basic physiology of VA ECMO, the mechanism of complications, and the simple management of VA ECMO.
Catheters ; Drainage ; Extracorporeal Membrane Oxygenation ; Extremities ; Heart Arrest ; Heart-Lung Machine ; Hemorrhage ; Ischemia ; Lung ; Membranes ; Oxygen ; Perfusion ; Physiology ; Postoperative Complications ; Pulmonary Edema ; Shock ; Shock, Cardiogenic ; Thromboembolism

OBJECTIVE: To investigate the effect of limb remote ischemic preconditioning (RIPC) on hepatic ischemia/reperfusion (IR) injury and the underlying mechanisms.
 METHODS: Rats were subjected to partial hepatic IR (60 min ischemia followed by 24 hours reperfusion) with or without RIPC, which was achieved by 3 cycles of 10 min-occlusion and 10 min-
reperfusion at the bilateral femoral arteries interval 30 min before ischemia. Some rats were treated with a new PPAR-γ inhibitor, T0070907, before RIPC.
 RESULTS: At the end of reperfusion, liver injury was significantly increased (increases in Suzike's injury score, AST and ALT release), concomitant with elevated oxidative stress (increases in MDA formation, MPO activity, as well as the decrease in SOD activity) and inflammation (increases in TNF-α and IL-6 levels, decrease in IL-10 content). RIPC improved liver function and reduced histologic damage, accompanied by the increased PPAR-γ activation and autophagosome formation as well as the reduced autophagosome clearance. The beneficial effects of RIPC were markedly attenuated by T0070907, an inhibitor of PPAR-γ.
 CONCLUSION RIPC exerts the protective effects on liver by activation of autophagy via PPAR-γ.
Animals ; Autophagy ; drug effects ; genetics ; physiology ; Extremities ; Interleukin-10 ; metabolism ; Interleukin-6 ; metabolism ; Ischemia ; Ischemic Preconditioning ; methods ; Liver ; injuries ; Liver Diseases ; prevention & control ; Oxidative Stress ; drug effects ; PPAR gamma ; antagonists & inhibitors ; Rats ; Reperfusion Injury ; prevention & control ; Tumor Necrosis Factor-alpha ; metabolism

BACKGROUNDWhether plasma can transfer the protective effect(s) of remote ischemic preconditioning (RIPC) between animals remains unresolved. We therefore investigated the effects of plasma collected 48 hours after transient limb ischemia on blood pressure recovery during myocardial ischemia reperfusion (IR) in homogenic rats.

METHODSPlasma was collected from Lewis rats, and the donor rats were randomly assigned to 2 groups: transient limb ischemia and control (n = 8 each). Transient limb ischemia was achieved by four cycles of 5-minute ischemia and 5-minute reperfusion by noninvasive ligation and deligation of the both legs using elastic rubber bands after anesthesia. In the control group, no ligation was performed. Forty-eight hours later, whole blood was collected, and the plasma spun off. Study Lewis rats underwent 30-minute left anterior descending coronary artery occlusion followed by 180-minute reperfusion, and were randomly assigned to 2 groups (group A and group B, n = 24 each), each further subdivided into 3 subgroups (n = 8 each). The subgroups of group A received normal saline (group A1) , plasma of control rats (group A2), plasma of transient limb ischemia rats (group A3) respectively at 1 hour before IR; the subgroups of group B received normal saline (group B1), plasma of control rats (group B2), plasma of transient limb ischemia rats (group B3) respectively at 24 hours before IR. BIOPAC systems were used to measure hemodynamics of rats during myocardial ischemiareperfusion.

RESULTSSystolic blood pressure (SBP) after IR in group B3 was different from that in groups B1 and B2 (B3 vs. B1, P = 0.007; B3 vs. B2, P = 0.039) at the beginning of reperfusion and 30 minutes after reperfusion. SBP was higher in group B3 than in groups B1 and B2 at the beginning of perfusion (B3 vs. B1, P = 0.010; B3 vs. B2, P = 0.002) and 30 minutes after reperfusion (B3 vs. B1, P = 0.001; B3 vs. B2, P = 0.001). SBP did not differ among subgroups A1, A2 and A3. Diastolic blood pressure and heart rate did not change in group A or group B.

CONCLUSIONSThe transfusion of plasma collected 48 hours after transient limb ischemia into homogenic rats 24 hours before IR can improve the SBP recovery during reperfusion. This may suggest that cardioprotective effect of late phase of RIPC is transferable via plasma.

Animals ; Blood Pressure ; physiology ; Extremities ; blood supply ; Ischemia ; Ischemic Preconditioning ; Male ; Plasma ; Rats ; Rats, Inbred Lew ; Time Factors

OBJECTIVETo verify whether peripheral blood circulation and arterial wall distensibility are influenced by atmospheric pressure (AtPr) and to examine if their association is dependent on age and/or sex.

METHODSAssociations among natural AtPr levels (on the examination day as well as 1 and 2 days prior), limb muscle hemodynamics, and distensibility of conduit arteries were retrospectively examined in an observational study of 276 untreated patients with primary moderate hypertension (mean age 56.4 years, 194 men). Forearm and calf circulations at rest and 3 min after ischemia were measured by venous occlusion plethysmography. Compliance of the brachial and shank arteries was assessed by oscillometry.

RESULTSAfter adjustment for age, degree of hypertension, and season, correlation and multiple regression analyses revealed a season-independent but age-dependent direct correlation between the stiffness of limb arteries and AtPr levels on the examination day in men, but not women. The association weakened with the degree of hypertension, disappeared with age, and was more evident in the arms than in the legs.

CONCLUSIONParameters of arterial wall distensibility in adult hypertensive men are susceptible to AtPr changes within the usually observed limits (730-770 mmHg). It is proposed that reduction of arterial wall barometric responsiveness in women and aging men is a likely mechanism underlying their meteosensitivity.

Adult ; Aged ; Aging ; physiology ; Atmospheric Pressure ; Cross-Sectional Studies ; Extremities ; blood supply ; Female ; Hemodynamics ; Humans ; Hypertension ; physiopathology ; Male ; Middle Aged ; Muscle, Skeletal ; blood supply ; Retrospective Studies ; Seasons ; Sex Characteristics ; Vascular Stiffness

OBJECTIVE: To investigate the liver protection mechanisms of MAPK signaling pathway of limb ischemia preconditioning in the late phase. METHODS: Thirty-six adult male New Zealand white rabbits, weighing 1.8-2.0 kg, were randomly divided equally into 3 groups: group C (sham operation), group L (liver ischemia-reperfusion 24 h after limb ischemia preconditioning), group IR (liver ischemia-reperfusion without limb ischemia preconditioning). Serum alanine transaminase (ALT) was measured during ischemia reperfusion. The tissue and cell injury of liver were examined by optical and electron microscopy. Activation of P38MAPK, P44/P42MAPK, and JNK in hepatic tissue was assessed by western blot after 30 min of reperfusion. RESULTS: Serum ALT and cell injury in the liver as examined by optical and electron microscopy was decreased in group L as compared with the group IR. Phosphorylation of P38MAPK, P44/ P42MAPK, and JNK were all increased significantly after 30 min of reperfusion. Phosphorylation of P38MAPK and JNK was reduced by limb ischemia pre-treatment. CONCLUSION Limb ischemia pre-treatment can induce the late phase of preconditioning in rabbit liver through the inhibition of the phosphorylation of P38MAPK and JNK.
Animals ; Extremities ; blood supply ; Ischemic Preconditioning ; methods ; Liver ; blood supply ; MAP Kinase Signaling System ; Male ; Phosphorylation ; Rabbits ; Reperfusion Injury ; prevention & control ; p38 Mitogen-Activated Protein Kinases ; chemistry ; physiology

OBJECTIVETo explore the protective effects of ischemic preconditioning (IPC) on the lung injury following with limbs ischemia /reperfusion (LI/R).

METHODSThe models of LI/R injury were constructed in rabbits. The blood from right external jugular vein and left common carotid artery, into and out-flowing pulmonary blood (IPB, OPB) respectively. Superoxide dismutase (SOD), malondialdehyde (MDA), nitric oxide (NO) in IPB and OPB and lung tissues were measured, as well as total nitric oxide synthase (tNOS) and inducible nitric oxide synthase (iNOS) in lung tissues were detected in different groups. The effects of IPC on the lung injury were observed.

RESULTSCompared with sham and before ischemic, the activity of SOD decreased and the content of MDA and NO increased after 4 h ischemia followed by 4 h reperfusion in IPB, OPB and lung tissues. The activity of tNOS and iNOS in lung tissues increased remarkably as well, there was statistical significance (P < 0.05, P < 0.01). SOD increased and MDA, NO, tNOS, iNOS decreased significantly by IPC before ischemia/reperfusion. The correlation analysis indicated that MDA was negatively correlated with SOD and was positively correlated with MDA, NO, iNOS (P < 0.01).

CONCLUSIONOxygen free radicals metabolic confusion of lung occurred in the course of LI/R, IPC could strengthen the resistance of peroxidation in lung and had protective effects on the lung injury following with LI/R.

Animals ; Extremities ; blood supply ; Female ; Ischemic Preconditioning ; methods ; Lipid Peroxidation ; physiology ; Lung Injury ; metabolism ; physiopathology ; prevention & control ; Male ; Nitric Oxide ; metabolism ; Nitric Oxide Synthase ; metabolism ; Rabbits ; Reperfusion Injury ; physiopathology ; Superoxide Dismutase ; metabolism

OBJECTIVE: To analyze and compare different methods for assessment of the limbs joints function and to discuss the rationality of the methods. METHODS: Eight hundred and six cases were collected from the Fujian Minzhong Forensic Appraisal Center from 2007 to 2010. These cases included injuries of large limbs joints with or without peripheral nerve injury. The loss of joint function was calculated according to the simple joint mobility method or the table method introduced in the book "Forensic Clinical Judicial Authentication Practice". The results of disability evaluation with different methods were analyzed and compared between different joints and injury patterns. RESULTS: In 642 cases of simple joint injuries without peripheral nerve injury, the results of disability evaluation based on simple joint mobility were the same as that based on the table. In 118 cases of joint injuries with peripheral nerve injury, all of them could be classified as disability, 33 cases (28.00%) had higher degree based on the table method than based on the simple joint mobility method. While 21 cases (17.80%) did not be evaluated as disabled based on the simple joint mobility method. CONCLUSION The evaluation for loss of limb function would be easier, more scientific and reasonable by the direct table method than the simple joint mobility method.
Accidents, Traffic ; Adult ; Arm Injuries/physiopathology* ; Disability Evaluation ; Extremities ; Female ; Forensic Medicine/methods* ; Humans ; Joints/physiopathology* ; Leg Injuries/physiopathology* ; Male ; Peripheral Nerve Injuries/physiopathology* ; Range of Motion, Articular/physiology* ; Trauma Severity Indices

Evaluation of limbs muscle function is one of the difficult tasks in forensic clinical medicine. Recently, there are more and more cases needed to be evaluated on the limbs muscle function in forensic clinical appraisal. Thus the assessment methods for muscle function have been concerned increasingly. This paper introduces the classification of muscle function and the type of muscle contraction, reviews the assessment methods for muscle function and their application value, such as manual muscle test, simple instrumental muscle test, isokinetic muscle test and electrophysiological test. It has also proposed to evaluate the muscle function with multiple methods comprehensively.
Biomechanical Phenomena ; Electromyography/methods* ; Exercise Test/methods* ; Extremities/physiology* ; Forensic Medicine ; Humans ; Isometric Contraction/physiology* ; Muscle Contraction/physiology* ; Muscle Strength/physiology* ; Muscle Tonus ; Muscle, Skeletal/physiology* ; Muscles/physiology*

OBJECTIVETo better assess the role of p38 MAPK, this project was designed to investigate whether intraventricular injection of antisense oligodeoxynucleotide (As-ODN) directed against the p38 MAPK of pyramidal neurons in hippocampus could affect the brain ischemic tolerance induced by limb ischemic preconditioning (LIP).

METHODSThe rat 4-vessel occlusion global cerebral ischemic model was used. Forty-eight male Wistar rats with permanently occlusion of the bilateral vertebral arteries were divided into 8 groups (n=6): sham, LIP, brain ischemic insult, LIP + brain ischemic insult, distilled water + LIP + brain ischemic insult, p38 MAPK As-ODN and p38 MAPK As-ODN + LIP + brain ischemic insult (two doses of 5 nmol/5 microl and 10 nmol/5 microl were used) groups. Thionin staining was used for observing histological changes of the hippocampus.

RESULTSNo significant delayed neuronal death (DND) was detected in the CA1 hippocampus of the rats that underwent sham and LIP operation. Brain ischemic insult for 8 min induced obvious DND as represented with the increase in histological grade (HG) and decrease in neuronal density (ND) significantly compared with sham and LIP groups. LIP protected the CA1 hippocampal pyramidal neurons against DND induced by global brain ischemic insult, suggesting the occurrence of brain ischemic tolerance. However, pretreatment with p38 MAPK As-ODN effectively blocked the ischemic tolerance induced by LIP in a dose dependent manner.

CONCLUSIONIt could be concluded that p38 MAPK plays an important role in the brain ischemic tolerance induced by LIP.

Animals ; Brain Ischemia ; physiopathology ; Cell Death ; Extremities ; blood supply ; Hippocampus ; pathology ; Ischemic Preconditioning ; methods ; Male ; Oligodeoxyribonucleotides, Antisense ; pharmacology ; Rats ; Rats, Wistar ; Reperfusion Injury ; prevention & control ; p38 Mitogen-Activated Protein Kinases ; metabolism ; physiology

AIMTo investigate the role of mitochondrial permeability transition pore (MPTP) in the cardioprotection by remote preconditioning (RPC).

METHODSRemote Precondition (RPC) was induced in anesthetized male Sprague-Dawley rats by three cycles of 5 min of right femoral artery occlusion followed by 5 min of reperfusion. Myocardial ischemia/reperfusion (I/R) injury was achieved by ligation of the left anterior descending coronary artery for 30 min and then reperfusion for 120 min. Infarct size was determined by 2,3,5-triphenyltetrazolium chloride (TTC) staining method. The level of lactate dehydragenase (LDH) in plasma and the opening of the mitochondrial permeability transition pore (MPTP) were measured.

RESULTSRPC significantly decreased the infarct size and plasma lactate dehydrogenase level induced by I/R, and these effects were attenuated by atractyloside (Atr, 5 mg/kg), a MPTP activator. However, administration of cyclosporin A (CsA, 10 mg/kg), an inhibitor of MPTP, decreased the effect of I/R. In isolated ventricular myocytes loaded with calcein, RPC decreased the MPTP opening, and this effect was attenuated by Atr (20 micromol/L).

CONCLUSIONInhibition of MPTP opening is involved in the cardioprotection by RPC.

Animals ; Extremities ; blood supply ; Ischemic Preconditioning ; methods ; Male ; Mitochondrial Membrane Transport Proteins ; physiology ; Myocardial Reperfusion Injury ; physiopathology ; prevention & control ; Rats ; Rats, Sprague-Dawley